Influenza, or commonly known as flu, is a contagious respiratory illness caused by influenza viruses. Influenza spreads around the world in seasonal epidemics, killing millions of people in pandemic years and hundreds of thousands in non-pandemic years. Typically, influenza is transmitted from infected mammals through the air and from infected birds through their droppings. Moreover, influenza infects many animal species, and transfer of viral strains between species can occur. Birds are thought to be the main animal reservoirs of influenza viruses.
Ways to prevent or inactivate influenza viruses in humans may include vaccination and anti-viral medications. An influenza vaccine is recommended for high-risk groups, such as children and the elderly, but the effectiveness of those influenza vaccines is variable. Due to the high mutation rate of the virus, a particular influenza vaccine usually confers protection for no more than a few years. Moreover, it is possible to get vaccinated and still get influenza. Anti-viral medication is sometimes effective, but viruses can develop resistance to even the standard anti-viral drugs, such as amantadine, rimantadine, zanamavir and oseltamivir.
Consequently, developing flu preventing and treating products with high efficacy are desirable. New and effective compositions are needed to prevent and treat the influenza viruses including avian flu viruses.